COGNITIVE NEUROSCIENCE:
Cognitive Neuroscience --Then and Now
Cognitive Neuroscience is the study of how the brain "thinks". Far from being a new field, this field of investigation has existed since the early 19th Century. The above left image, of a "phrenology" head illustrates the early "scientific" attempts to formulate ideas and theories about thought and behaviour. Initially, it was believed that the topology of the skull (its lumps and bumps) had to do with cognition. Luckily, a number of 19th Century physicians and scientists challenged the views of phrenology, carrying out experiments on animal and human brains. In doing so, especially from dissecting the brains of individuals who had suffered epilepsy (and also by deliberately causing lesions in the brains of living animals) much began to be discovered about how the human brain is structured, and which areas are involved in different behaviours.
As technology and academic integrity in science progressed, so did this fascinating field. One of the areas of cognitive neuroscience involves researching the areas of the brain responsible for communication. (This is one of Dr. Grossi's areas of research).
Our ability as human beings to use language to convey concrete and abstract concepts to one another is what sets us apart from every other animal on this planet. The human brain contains unique structures that are specialized for this complicated task.
In 1861, a physician named Paul Broca recorded the case of a man who had suffered a stroke and could no longer produce meaningful speech. It was discovered that the man had suffered severe damage to a section of his left temporal lobe, which is now known as "Broca's Area" --the area involved in producing speech. My father had a stroke, and as a result suffered severe Broca's Aphasia. He was unable to speak, although he retained much of his ability to comprehend written and spoken language. After diagnosis by a neurologist who conducts MRI brain imaging to locate the areas of damage, Broca's Aphasia is treated by Speech and Language Pathologists, who work with stroke survivors to help their damaged brains "re-learn" to speak, and also work to help these individuals master alternative methods of communication such as sign language, which is processed in a different part of the cortex.
Similarly, a physician named Wernicke encountered a stroke survivor who could produce language, yet it was entirely meaningless strings of words. The patient had lost receptive language skills. Damage to different area of the brain, now known as Wernicke's Area (located farther back in the temporal lobe) resulted in very different profound language impairment. Wernicke's Aphasia patients present a challenge to Speech and Language Pathologists because they are unable to comprehend instructions.
In 1870, German physicians ran an electrical current through the cortex of dogs causing them to produce characteristic movements based on where the current was applied. Since different areas produced different movements, the physicians concluded that behavior was rooted at the cellular level. Further to this, German neuroanatomist Korbinian Brodmann stained the brain tissues, finding that there were different types of cells in the brain, and that different areas of tissue controlled different functions. He concluded in 1909 that there were 52 distinct areas, now named "Brodmann Areas." The illustrations below show the differentiated functions of these areas.
Clearly then, cognitive neuroscience is one of the most exciting fields of neuroscience research. Apart from encompassing linguistics, it also addresses areas such as learning, memory and consciousness. As we embark upon our journey into the 21st Century, advances in Cognitive Neuroscience will help us on our quest to understand the very elements that make us human.
--Jenn Gilligan
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